1. Technical Field
The present application relates to an apparatus for suturing body tissue, and more particularly, to an apparatus which passes a surgical needle between its jaws and a disposable loading unit for loading a needle into the jaws.
2. Background of Related Art
During both open and minimally invasive (endoscopic) surgical procedures, suturing of body tissue can be time consuming for the surgeon. In endoscopic procedures, where surgery is performed in a body cavity and access to the site is through trocar cannulas, suturing is especially difficult. The surgeon cannot grasp the needle in his hand as in open surgery, but must rely on grasping instruments to grasp and maneuver the needle in the remote surgical site. These instruments entail grasping the surgical needle between the instrument jaws and manipulating the needle through the body tissue. Oftentimes, a second grasping instrument is required to enable passing the needle between the two instruments in the same manner the surgeon passes the needle between his hands during open procedures. Not only is maneuverability difficult, but the needle could slip from the jaws into the body cavity.
To this end, the instrument disclosed in EPO application 92308849.6 was developed. This instrument advantageously provided the surgeon with unprecedented control during suturing in endoscopic procedures. The surgical needle is passed between the jaws of the instrument and is retained in one of the jaws as they are opened. This instrument provided a marked advance over the earlier laparoscopic/endoscopic techniques of suturing. An improvement to the instrument disclosed in EPO Patent Application No. 92308849.6 is disclosed in U.S. patent application Ser. No. 08/134,145, filed Oct. 8, 1993, now abandoned. One of the advantages of this later instrument is it provided a disposable loading unit which enabled the needle and suture to be removed from the apparatus and reloaded with a fresh needle and suture.
The advantages attendant passing and retaining a surgical needle between instrument jaws is not limited to endoscopic applications. For example, in open vascular surgery, due to the extremely small size of the surgical needles, it is sometimes difficult for the surgeon to manipulate the needles between his/her hands. Additionally, the surgery is often done under magnification and the surgeon's repeated focus on the surgical site to pass the needle through the tissue, focus away from the surgical site to pass the needle between his hands in preparation for the next stitch, and then re-focus on the surgical site to continue stitching, is tiring and can cause eye strain. An instrument which passes the needle between the jaws overcomes these difficulties by allowing the surgeon to continuously focus on the surgical site during the entire vessel stitching procedure.
It would be advantageous to provide a suturing instrument which would enable a needle to be retained and passed between its jaws. It would further be advantageous to provide such an instrument that enabled quick and easy reloading of a fresh needle and suture, and could accommodate needles and sutures of various sizes/configurations and materials.